Surely the most important dismissal ever should be of some lasting significance (important misses is surely a separate thread) in the history of the game not a random dismissal of little consequence beyond the time in which it happened.

Gatting's reverse sweep in the 1987 WC final, which decided the game and set up Aus' recovery from the mid80's and paved the way eventual world domination. Without Fat Gatt's brainstorm, none of that would ever have happened.